i am slowly getting parts together for my mild engine build and i was thinking about sending the injector tips out to get honed or edm'd; which do you guys think is better?
edm or extrude honed? which is better for injector tips?
- Thread starter dmaxvaz
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super diesel
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Guy would probably be better to answer this but this is what I've seen. Guys with EDMed injectors smoke more and I think it's because of the bigger holes, same amount to slightly less injection pressure = less atomization = less of the total burn of the injected diesel droplets. Extrude is what I have and seems to atomize well. However I like to increase flow and pressure with this move to optimize the compleat fuel burn. The larger the holes are, the higher (IMHO) the pressure needs to be to fully atomize the shot. I don't know if this holds water, but this is what I've always believed with the Dmaxes to get full potential out of the fuel being squeezed in. I'm quite sure opinions will vary on this. This is just mine. No stone throwing please.
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i thought thay it didnt matter, and that they are just procedures on enlarging the holes one is enlarged by an abrasive fluid or paste and one is enlarged by eroding it away by electronic spark? what the hell do i know?i thought extrude honed were the ones with the bigger holes?
i like the ones that volker makes, 100% over but still the same size holes. theres just 14 of them
yeah, but does he do this anymore? i called him the other day and he told me he is giving skiing lessons and he will call me back that night- never happened
super diesel
<<<< Under Pressure
I believe the stock holes are around .0064-.0067 or so on the LB7s (Pat correct me if I'm wrong on this). If you go to a .0085 (or there abouts) it will flow 100% more. I had a old friend who is a M.E. figure it up. I don't have my charts any more (stolen), so I don't remember exact figures. I've done EDMing for about 20+ years now. The smallest I've made a trode is about .010 and I could burn a .012 hole. There are slightly finer trodes available now from what I understand (I never needed anything this small). The Extrude flows (pushes) a rough polishing fluid through the holes to open them up. They do need to be checked for balance between them after any of these procedures. Guy (SoCal) does this as well.
Think about what 20% overs with 20% more pressure would do.
Think about what 20% overs with 20% more pressure would do.
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The guy that does all of our small edm'ing can do holes as small as .002 he says. I just called him. He has done .004" holes for us in the past.
SD were you holding that in a collet?
The LLY injectors are smaller than LB7, IIRC.
Thanks for the info.
SD were you holding that in a collet?
The LLY injectors are smaller than LB7, IIRC.
Thanks for the info.
super diesel
<<<< Under Pressure
.002? or .002 over the trode size? .004 is hard to imagine. This is average human hair dia.
No. This was being held in a holding fixture I made.
Yes. From what I remember Pat saying a while back the LLYs are smaller than the LB7s.
Yes .004 is the diameter of the hole he burned. We now drill the hole (finally bought a mill accurate enough to do the job) There is a .005" protrusion on the part and we drill a .004" hole thru the center. The edm didn't work out as well as I had hoped. AFAIK, this peice weaves small fibers.
Edit: it is a cylinderical part and all of the machining is done on a mill. Just for the added cool factor
. Never could get a lathe to make the part within tolerance, not even the latest mori's..
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